1. Field of Invention
The present invention relates to a communication control method and a control program, and relates more particularly to a communication control method and a control program that enable an application program that is compatible with a specific communication interface to connect to another communication interface that is different from the specific communication interface.
2. Description of Related Art
In order to use various peripheral devices that are accessible through the operating system, application programs typically incorporate various device drivers, which are software modules for controlling particular peripheral devices. See, for example, Japanese Unexamined Patent Appl. Pub. JP-A-2008-158785.More specifically, a device driver is software for handling input and output between an application program and a particular device, and for controlling input/output devices (hardware such as expansion cards and peripheral devices) such as graphic display devices, printers, and Ethernet® boards.
Configurations and methods that communicate with a physical communication port through a virtual port driver that primarily handles control of the communication protocol are also used in order to efficiently produce and use device drivers. In a communication environment having multiple virtual port drivers that all use the same physical communication port, competition occurs amongst at least some of the virtual port drivers for use of the same communication port at the same time or during the same time frame.
Depending upon the type or design of the virtual port driver, the virtual port driver may also continue to occupy the communication port to which it is connected once it secures a connection to the communication port. An example of this type of virtual port driver is, more specifically, a virtual port driver that constantly checks the connection status once communication is established. This type of virtual port driver does not release the communication port because it must constantly determine if the controlled device is connected to the communication port to which the virtual port driver is connected.
Therefore, if one virtual port driver is thus occupying the communication port and a second virtual port driver attempts to use the same communication port, the second virtual port driver will not be able to use the communication port. This means that a device driver (application program) that connects to the communication port through the second virtual port driver will not be able to use the communication port.